js-rigor: lossless persistence — validity, decay config, and TTLs survive snapshots

The persistence probe found three silent-loss defects in the snapshot
round trip: relation validity labels (finite_sample downgraded to
heuristic after save/load!), decay configs, and the value manager's
per-relation TTL settings all vanished. The restored arbiter built its
indices directly from the condensed graph, whose edge channel carries
possibility/reliability/value only.

Format version 2 now carries per-relation metadata (validity, decayConfig)
and the valueTtls table in the snapshot payload; both the snapshot-access
layer and the CondensedGraphIndices build merge the metadata back, so a
restored arbiter is lossless end to end. Version 1 buffers are rejected
with the existing clean version error.

Pinned: a persistence round-trip test asserting validity label, decay
config, TTL, and the restored check's validity label. Suites: rigor
207/0, full 809/747/0.

src/core/SnapshotBinary.js

@@ -18,10 +18,15 @@ function toSnapshotSafe(value, stripKeys) {
   }));
 }
 
+// Format version 2: per-relation metadata (validity, decayConfig) and the
+// per-relation TTL settings are carried in the JSON payload. Version 1
+// buffers are rejected with a clean error, never misparsed.
+const SNAPSHOT_VERSION = 2;
+
 function serializeArbiterSnapshot(arbiter, options = {}) {
   const writer = new BinaryWriter();
   writer.writeUint32(MAGIC);
-  writer.writeUint32(1);
+  writer.writeUint32(SNAPSHOT_VERSION);
 
   const graph = options.graph || arbiter.snapshotGraph;
   if (!graph) {
@@ -54,10 +59,37 @@ function serializeArbiterSnapshot(arbiter, options = {}) {
     });
   }
 
+  // Per-relation metadata that the condensed graph edge channel does not
+  // carry: validity labels and decay configs must survive persistence, or
+  // a labeled relation silently downgrades to heuristic after a save/load
+  // cycle. Keyed by the graph's numeric ids (stable within the snapshot).
+  const relationMetadata = {};
+  for (const rel of arbiter.relations || []) {
+    if (!rel || rel.src === undefined || rel.dst === undefined || !rel.rel) continue;
+    const key = `${rel.src}|${rel.rel}|${rel.dst}`;
+    if (rel.validity !== undefined || rel.decayConfig !== undefined) {
+      relationMetadata[key] = {
+        ...(rel.validity !== undefined ? { validity: rel.validity } : {}),
+        ...(rel.decayConfig !== undefined ? { decayConfig: rel.decayConfig } : {})
+      };
+    }
+  }
+
+  // Per-relation TTL settings are runtime value-manager state; without them
+  // a restored arbiter silently applies the default TTL to every relation.
+  const valueTtls = {};
+  if (arbiter.valueManager && arbiter.valueManager.ttlConfigs) {
+    for (const [relation, ttl] of arbiter.valueManager.ttlConfigs.entries()) {
+      valueTtls[relation] = ttl;
+    }
+  }
+
   const snapshot = {
     relations: relationEntries,
     relationIdSnapshot: arbiter.keyManager.getRelationIdSnapshot(),
-    nodes: nodeEntries
+    nodes: nodeEntries,
+    relationMetadata,
+    valueTtls
   };
 
   const json = JSON.stringify(snapshot);
@@ -72,7 +104,7 @@ function deserializeArbiterSnapshot(buffer, arbiterFactory) {
   const magic = reader.readUint32();
   if (magic !== MAGIC) throw new Error('Invalid arbiter snapshot');
   const version = reader.readUint32();
-  if (version !== 1) throw new Error(`Unsupported arbiter snapshot version ${version}`);
+  if (version !== SNAPSHOT_VERSION) throw new Error(`Unsupported arbiter snapshot version ${version}`);
 
   const graphLength = reader.readUint32();
   const graphBytes = reader.readBytes(graphLength);
@@ -135,6 +167,18 @@ function deserializeArbiterSnapshot(buffer, arbiterFactory) {
     }
   }
 
+  // Restore the metadata the edge channel cannot carry (consulted by the
+  // snapshot access layer when it materializes relation objects).
+  arbiter._snapshotRelationMetadata = (payload.relationMetadata && typeof payload.relationMetadata === 'object')
+    ? payload.relationMetadata
+    : {};
+
+  if (payload.valueTtls && typeof payload.valueTtls === 'object' && arbiter.valueManager) {
+    for (const [relation, ttl] of Object.entries(payload.valueTtls)) {
+      arbiter.valueManager.setTTL(relation, ttl);
+    }
+  }
+
   return arbiter;
 }
 

src/core/arbiter/ArbiterSnapshot.js

@@ -56,7 +56,9 @@ export class ArbiterSnapshot {
     const arbiter = deserializeArbiterSnapshot(buffer, () => createArbiter(options));
     if (arbiter.snapshotGraph) {
       if (options.buildSnapshotIndices !== false) {
-        arbiter.indices = new CondensedGraphIndices(arbiter.snapshotGraph);
+        arbiter.indices = new CondensedGraphIndices(arbiter.snapshotGraph, {
+          relationMetadata: arbiter._snapshotRelationMetadata || null
+        });
         arbiter.indicesBuilt = true;
       } else {
         arbiter.indicesBuilt = false;

src/core/graph/CondensedGraphIndices.js

@@ -1,6 +1,7 @@
 export class CondensedGraphIndices {
-  constructor(graph) {
+  constructor(graph, options = {}) {
     this.graph = graph;
+    this._relationMetadata = options.relationMetadata || null;
     this.outgoingEdges = new Map();
     this.incomingEdges = new Map();
     this._relationsByRelId = new Map();
@@ -77,6 +78,14 @@ export class CondensedGraphIndices {
         stateId: `snapshot-${edgeIdx}`
       };
 
+      // Merge per-relation metadata (validity, decay config) so the
+      // restored indices are lossless, not just the snapshot access layer.
+      const meta = this._relationMetadata ? this._relationMetadata[`${srcId}|${relName}|${dstId}`] : null;
+      if (meta) {
+        if (meta.validity !== undefined) relation.validity = meta.validity;
+        if (meta.decayConfig !== undefined) relation.decayConfig = meta.decayConfig;
+      }
+
       this._relations[edgeIdx] = relation;
 
       const relSet = this._relationsByRelId.get(relId);

src/core/relation/RelationSnapshotAccess.js

@@ -79,7 +79,7 @@ export class RelationSnapshotAccess {
     const relBits = graph.adjacency
       ? graph.adjacency[edgeIdx * 6 + 4]
       : graph.edgeReliabilityBits[edgeIdx];
-    return {
+    const result = {
       src: srcId,
       rel: relationName,
       relId,
@@ -91,5 +91,16 @@ export class RelationSnapshotAccess {
       changed_last_at: graph._builtAt || Date.now(),
       source: 'snapshot'
     };
+    // Merge per-relation metadata the edge channel does not carry (validity
+    // labels, decay configs) so persistence is lossless.
+    const metaKey = `${srcId}|${relationName}|${dstId}`;
+    const meta = this.manager.arbiter._snapshotRelationMetadata
+      ? this.manager.arbiter._snapshotRelationMetadata[metaKey]
+      : null;
+    if (meta) {
+      if (meta.validity !== undefined) result.validity = meta.validity;
+      if (meta.decayConfig !== undefined) result.decayConfig = meta.decayConfig;
+    }
+    return result;
   }
 }